*{
    margin: 0;
    padding: 0;
}
body{
    min-width: 800px;
    overflow-x: hidden;
}

@media (max-width: 799px){
    body{font-size: 14px}
} /*<=799的设备*/
@media (min-width: 800px){
    body{font-size: 16px}
} /*>=800的设备*/
@media (min-width: 1024px){
    body{font-size: 18px}
} /*>=1024的设备*/
@media (min-width: 1100px) {
    body{font-size: 20px}
} /*>=1100的设备*/
@media (min-width: 1280px) {
    body{font-size: 22px;}
} /*>=1280的设备*/
@media (min-width: 1366px) {

    body{font-size: 24px;}
}
@media (min-width: 1440px) {
    body{font-size: 25px !important;}
}
@media (min-width: 1680px) {
    body{font-size: 28px;}
}
@media (min-width: 1920px) {
    body{font-size: 32px;}   /*1em=32px*/
}
.main_box{
    width: 100%;
}
.header{
    height:1.31em ;
    background-color: black;

}
.header_rignt{
    width: 31.18%;
    height:1.31em ;
    float: right;
}
.header_rignt ul li {
    float: left;
    line-height: 1.31em;
    list-style: none;
    margin-left: 2.5%;
}
.header_rignt ul li a{
    /*15px*/
    font-size: 0.45em;
    text-decoration: none;
    color: white;
}
.nav{
    width: 100%;
    height: 3.93em;
    /*border: 1px solid black;*/
}
.nav_logo{
    width: 23.28%;
    height:3.93em ;
    /*border: 1px solid black ;  447px*/
    float: left;
}
.nav_logo_tu{
    float: right;
    width: 20.58%;
    height: 2.06em;
    background-image: url("../images/logo_03.png");
    background-size: cover;
    margin-top: 0.9em;
}
.nav_center{
    width: 36.56%;
    height:3.93em ;
    /*border: 1px solid black;*/
    float: left;
}
.nav_center ul li{
    float: left;
    list-style: none;
    height:3.93em ;
    line-height: 3.93em ;
    margin-left: 4.73%;
}
.nav_center ul li a{
    font-size:0.46em ;
    text-decoration: none;
    color: black;
}
.nav_center_active{
    color: #c53e3b !important;
    background-color: yellow;
}
.nav_right{
    /*749px  125px */
    width: 39%;
    height:3.93em ;
    float: right;
}
.header_rignt_box{
    margin-top: 1.15em;
}
.banner{
    width: 100%;
    height: 28em;
    background-image: url("../images/dingzhi_03_02.png");
    background-size: cover;
}
.box{
    width: 13.3%;
    height: 1.59em;
    position: absolute;
    left: 77%;
    top: 26.7em;
    border: 1px solid black;
}
.contan_top{
    width: 100%;
    height: 11em;
    background-color: #e6e8e8;
}